Known in the prior art is a device for taking samples of bottom sediments from water basins, comprising a vertical coring tube with a closed upper end provided with a check valve, a ballast weight in the lower portion of the coring tube around the outside walls thereof (cf. USSR Inventor's Certificate No. 623,128, class G01N, 1/04, published in 1978).
When this device is free-falling on the load rope to the bottom of a water basin by gravity, the integrity of a surface layer of the bottom sediments is disturbed which impairs the quality of a taken sample. In addition, the sample cannot be extracted from the coring tube of the given device in the form of thin layers.
Also known to the prior art is a device for taking samples of bottom sediments from water basins, comprising a vertical sectional tube with a closed upper end provided with a check valve, a ballast weight on the outside surface of the closed upper end having removable ballast disks, and rod-type vertical supports externally arranged on the sides of the coring tube (cf.USSR Inventor's Certificate No. 1,013,810, class G01N, 1/10, published in 1983).
This device makes it possible to remove the taken sample in thin layers by way of a successive detachment of the coring tube sections. The presence of the rod-type vertical supports prevents tipping of the coring tube when it interacts with the soil and the removable disks of the ballast weight make it possible to partially regulate the speed of the device sinking. However the known device fails to provide, especially under adverse weather conditions, a smooth contact of the coring tube with the bottom of a water basin and an approach of the device to the bottom at a minimum speed (less than 25 cm/s) insuring reliability of the sample taken without disturbing the layers of the initial structure of bottom sediments.
The invention seeks to improve the design of a device for taking samples of bottom sediments from water basins so that it will have a means for insuring a smooth contact of the device with the bottom of a water basin without disturbing the integrity of a surface layer of the bottom sediments even under adverse weather conditions.